One of the most interesting aspects of mind wandering is that it has documented links to both beneficial and costly aspects of psychological functioning. For example we are all probably familiar with the experience of trying to read a book and then suddenly noticing that while our eyes have been moving across the words on the page, our minds have been elsewhere. Given the importance of education, the consequences of mind wandering while reading could be a cause for concern. On the other hand we also probably recognise that sometimes we find that we are suddenly caught up in a compelling line of thought that provides clarity on a problem that has been bugging us for a long time. As creativity is an important aspect of human productivity, this observation should draw attention to the value that mind wandering can bring to a persons life. It is this complex balance of cost and benefits that makes understanding the mind wandering state both intriguing psychologically and important scientifically.

In a recent paper co-authored with Jessica Andrews-Hanna from the University of Colorado Boulder, we proposed that the reason that this seeming contradiction arises is because prior studies have failed to take into account important features of the mind wandering state. One important aspect which we believe impacts on the costs and benefits of mind wandering in daily life is its content. Thinking about how a meeting may go, or where to go on holiday are probably quite normal and helpful because they exploit our mental capacity to self-generate thoughts in way that means that events in the future might go more smoothly. On the other hand ruminating about past failures, or incessantly thinking about how things could go wrong are less likely to be helpful, and may in fact exacerbate states of worry or unhappiness. One idea we proposed is that the content of mind wandering may be important in determining whether it is beneficial to an individuals well being.

A second boundary condition that determines whether mind wandering has costs or benefits is the context within which the experience unfolds. One well documented consequence of mind-wandering is that it can derail performance of an external task. Thus while certain internal musings might be appropriate while taking a shower or while waiting in line to buy a coffee, these experiences are probably to be avoided when operating heavy machinery or taking an exam. In demanding contexts mind wandering can jeopardise the safe performance of the task, while in other contexts which do not require the same amount of attention these experiences will have less risk associated with them.

In our paper published in Frontiers in Psychology (http://www.frontiersin.org/Perception_Science/10.3389/fpsyg.2013.00441/abstract) we argue that taking into account the content of mind wandering and the context in which it takes place are likely to be important in interpreting whether this experience is valuable to a person, or is instead a cause of psychological, or even physical pain. Our hope is that this basic idea will help move forward work on mind-wandering and help provide a more comprehensive explanation for this important, yet poorly understood mental phenomena.